Laminated strand lumber (LSL) reinforced by GFRP; mechanical and physical properties

- The effect of GFRP and resin types on technical properties of LSL studied.
- Results confirmed that resin type and glass fiber have significant effects on the properties.
- The most beneficial effect of GFRP was on MOR, MOE, impact, shear and compression strengths respectively.
- Based on the results, bending strength, modulus of elasticity were improved by 123 and114%, respectively.
- GFRP layers led to alteration of fracture place from tension side to compression side.

The effect of glass fiber reinforced polymer (GFRP) on the technical properties of LSL made from poplar (Populus deltoids L.) employing pMDI and UF as binders was investigated. Technical properties such as modulus of rupture (MOR), Modulus of elasticity (MOE), shear strength (SS), compression strength parallel to the grains (CS //), impact strength (IS), water absorption (WA) and thickness swelling (TS) were determined. Results confirmed that resin type and GFRP have significant effects on the LSL properties. It was revealed that the most beneficial effect of GFRP is on MOR, MOE, IS, SS and CS respectively. The Highest properties were obtained by using pMDI as the resin and GFRP as the reinforcement, where properties such as MOR, MOE, IS, SS and CS were improved by 123, 114, 100, 94, and 90%, respectively, compared to control samples. Furthermore, GFRP incorporation led to alteration of fracture place from tension side to compression side. Depending on the treatment type, the WA and TS values of the LVLs improved between 23% to 68% and 19.5% to 78%, respectively.